pm1772en allison

5/19/2018 PM1772EN Allison

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PM1772EN

PreventiveMaintenance

CL(B)T/HT 750 SeriesOil Field Applications


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Allison TransmissionVOCATIONAL MODELS

Preventive

Maintenance

1985 MAYRev. 1 2000 January

PM1772EN

CLT 750

CLBT 750

CLBT 750DB

HT 750DR

HT 750DR DB

Printed in USA Copyright 2007 Allison Transmission, Inc.


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WARNINGS, CAUTIONS, AND NOTES

IT IS YOUR RESPONSIBILITY to be completely familiar with the warnings and

cautions described in this handbook. It is, however, important to understand that

these warnings and cautions are not exhaustive. Allison Transmission could not

possibly know, evaluate, and advise the service trade of all conceivable ways inwhich service might be done or of the possible hazardous consequences of each

way. Consequently, Allison Transmission has not undertaken any such broad

evaluation. Accordingly, ANYONE WHO USES A SERVICE PROCEDURE OR

TOOL WHICH IS NOT RECOMMENDED BY ALLISON TRANSMISSION

MUST first be thoroughly satisfied that neither personal safety nor equipment safety

will be jeopardized by the service methods selected.

Proper service and repair is important to the safe, reliable operation of the

equipment. The service procedures recommended by Allison Transmission anddescribed in this handbook are effective methods for performing service operations.

Some of these service operations require the use of tools specially designed for the

purpose. The special tools should be used when and as recommended.

Three types of headings are used in this manual to attract your attention. These

warnings and cautions advise of specific methods or actions that can result in personal

injury, damage to the equipment, or cause the equipment to become unsafe.

TRADEMARKS USED

Loctiteis a registered trademark of the Loctite Corporation

Teflonis a registered trademark of the DuPont Corporation

Vitonis a registered trademark of the DuPont Corporation.

WARNING:A warning is used when an operating procedure, practice,etc., if not correctly followed, could result in personal injury or loss of life.

CAUTION:A caution is used when an operating procedure,practice, etc., if not strictly observed, could result in damage to ordestruction of equipment.

NOTE: A note is used when an operating procedure, practice, etc., is

essential to highlight.


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TABLE OF CONTENTS

Paragraph Description Page

Section I REMOVING TRANSMISSION FROM VEHICLE

11. Draining Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

12. Disconnecting Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

13. Uncoupling From Driveline And Engine. . . . . . . . . . . . . . . . . . 2

14. Removing Mounting Bolts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

15. Removing The Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

16. Removing Input And Output Flange Or Yokes . . . . . . . . . . . . . 3

17. Rebuild/Overhaul Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Section II PREPARING TRANSMISSION FOR INSTALLATION

21. Checking Flywheel (Engine-Mounted Models). . . . . . . . . . . . . 4

22. Installing Brake And Output Flange . . . . . . . . . . . . . . . . . . . . . 4

23. Installing Input Flange (Remote-Mounted) . . . . . . . . . . . . . . . . 5

24. Installing Range Selector Lever. . . . . . . . . . . . . . . . . . . . . . . . . 5

25. Installing PTO (Applicable at Any Location) . . . . . . . . . . . . . . 6

26. Installing Shift Modulation Control. . . . . . . . . . . . . . . . . . . . . . 627. Installing Oil Filler Tube . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Section III PREPARING VEHICLE FOR TRANSMISSIONINSTALLATION

31. Checking Flexplate Drive Assembly

(Transmission Engine-Mounted) . . . . . . . . . . . . . . . . . . . . . . . . 8

32. Checking Input Drive Components(Transmission Remote-Mounted) . . . . . . . . . . . . . . . . . . . . . . . 8

33. Checking Chassis And Driveline . . . . . . . . . . . . . . . . . . . . . . . . 9

34. Oil Cooler, Oil Filter, And Lines . . . . . . . . . . . . . . . . . . . . . . . . 9

35. Checking Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Section IV INSTALLING TRANSMISSION INTO VEHICLE

41. Handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

42. Mounting To Engine (Transmission Engine-Mounted). . . . . . 11

43. Installing Transmission Mounting Components . . . . . . . . . . . 12

44. Rear Support Of The CLBT 750DB . . . . . . . . . . . . . . . . . . . . 12

45. Coupling To Engine (Transmission Remote-Mounted). . . . . . 13


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Section IV INSTALLING TRANSMISSION INTO VEHICLE (contd)

46. Coupling To Driveline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

47. Connecting Cooler And Oil Filter Lines . . . . . . . . . . . . . . . . . 14

48. Connecting Range Selector Control. . . . . . . . . . . . . . . . . . . . . 16

49. Connecting Hydraulic Retarder Control (CLBT Models) . . . . 17

410. Connecting Modulator Control . . . . . . . . . . . . . . . . . . . . . . . . 17

411. Connecting Power Takeoff Controls . . . . . . . . . . . . . . . . . . . . 20

412. Connecting Parking Brake Controls . . . . . . . . . . . . . . . . . . . . 21

413. Connecting Output Disconnect Controls

(Dropbox Models Only). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

414. Connecting Speedometer Drive . . . . . . . . . . . . . . . . . . . . . . . . 21

415. Installing Temperature And Pressure

Sensors And Electrical Components . . . . . . . . . . . . . . . . . . . . 21

416. Filling The Oil System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

SECTION V OIL SYSTEM

51. Filling The System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

52. Deep Oil Pan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2353. Oil Pan Interchangeability . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

54. Spare Parts Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

55. Installation Of The 812Inch Transmission Oil Pan Assembly

and Oil Filler Tube. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

56. Oil Level And Oil Dipstick . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

57. Checking Transmission Oil Level . . . . . . . . . . . . . . . . . . . . . . 27

58. Oil Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2859. Oil Change And Filter Replacement . . . . . . . . . . . . . . . . . . . . 28

510. Oil Operating Temperatures. . . . . . . . . . . . . . . . . . . . . . . . . . . 29

511. Oil Level For Transfer Gear Housing (Dropbox) . . . . . . . . . . 29

Section VI DUAL MODE OPERATION

61. General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

62. Functional Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

63. Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

64. Downshift Inhibiting CL(B)T 750 (2100 And 2300 rpm

Dropbox Models Only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

65. CLBT 750 Dual Mode Transmission With Dropbox. . . . . . . . 36


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Section VII RELEASE OF STEP GOVERNOR VALVE BODYASSEMBLY P/N 23010297

71. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

72. Interchangeability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

73. Spare Parts Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Section VIII MANUAL/AUTOMATIC OPERATION ON OIL FIELDEQUIPMENT

81. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

82. Mannesmann Rexroth Corporation Shifter . . . . . . . . . . . . . . . 38

83. Bennett Shifter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

84. Preventive Maintenance On Shifters . . . . . . . . . . . . . . . . . . . . 46

85. Mode Shift Valves Used In Mannesmann Rexroth And

Bennett Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Section IX TROUBLESHOOTING CLBT 750 WITH DUAL MODE

91. Pressure Tap Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

92. Troubleshooting Dual Mode Circuitry. . . . . . . . . . . . . . . . . . . 5193. Step Governor Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55


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NOTES


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11. DRAINING TRANSMISSION

The transmission should be drained before it is removed from the vehicle.

Remove the oil drain plug from the rear of the transmission oil pan. Examinethe drained oil for evidence of water or debris that indicates failure of internal

components.

Reinstall the oil drain plug.

Remove the oil fill tube assembly if it will interfere during transmissionremoval.

Disconnect all oil lines from the transmission. Remove the lines from thevehicle if they will interfere during transmission removal. Plug openings to

keep dirt from entering the oil system.

12. DISCONNECTING CONTROLS

Controls, if not completely removed, should be disconnected from the transmission

and positioned so they do not interfere with transmission removal.

Disconnect all linkage or cables for shifting, shift modulation, hydraulicretarder operation, parking brake, and speedometer.

Remove the modulator and the modulator actuator rod (if loose intransmission housing) from the transmission.

Disconnect the power takeoff from its driven equipment. Disconnect the PTOcontrols. Remove the PTO completely if it will interfere with transmission

removal. Disconnect any electrical leads or capillary tubes to the neutral start switch,

reverse signal, solenoid valves, heaters, or pressure and temperature sensors.

NOTE: If not already marked, put a center-punch mark on the splined

transmission range selector lever, adjacent to the index mark on the

selector shaft, before removing the lever.

REMOVINGTRANSMISSION FROM

VEHICLE

SECTION

I


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13. UNCOUPLING FROM DRIVELINE AND ENGINE

Disconnect the vehicle driveline from the transmission output flange or yoke.Disconnect the input drive flange or yoke (remote-mounted). Position the

disconnected shafts to avoid interference with transmission removal.

Figure 11 shows a typical method of coupling the engine and transmission(engine-mounted). Remove the drive bolts that secure the flexplate to theconverter drive cover.

Figure 11. Typical Method of Coupling Transmission-to-Engine

14. REMOVING MOUNTING BOLTS

If the transmission mountings support the rear of the engine, place a jack orother support under the engine.

Support the transmission securely on a jack, hoist, or other removal

equipment. Remove all bolts, spacers, and supports that attach the transmission to the

engine and vehicle.

FLEXPLATE ASSEMBLY

INNER WEAR PLATE

FLEXPLATE-TO-ADAPTER BOLT

ADAPTER-TO-CRANKSHAFT BOLT

CRANKSHAFT HUB ADAPTER

FLYWHEEL HOUSING

CRANKSHAFT

STARTER RING GEAR

FLYWHEEL

DRIVE BOLT (12)

V02376.01

CONVERTERHOUSING

3.451 in. (87.67 mm)3.554 in. (90.27 mm)


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15. REMOVING THE TRANSMISSION

Move the transmission away from the engine until completely clear of theengine.

Raise or lower the transmission as required to remove it from the vehicle.

16. REMOVING INPUT AND OUTPUT FLANGES OR YOKES

When replacing the transmission, it may be necessary to transfer input and output

flanges or yokes to the replacement transmission. If the flanges or yokes are retained

by a large self-locking nut, specific procedures must be followed for removal of the

nut.

Before removing the nut, clean the output shaft threads to remove dirt and

contamination. Remove any burrs or thread damage that may be present.

If there are less than five notches or none at all, loosen the nut until there isabout 116inch gap between the nut and flange.

The first time the retaining nut is removed from the shaft, it must take aminimum of 400 lb in. (45 Nm) to rotate the nut from the shaft. Each

subsequent time the nut is removed, it must require a minimum of 300 lb in.

(34 Nm) to rotate it from the shaft. The torque value must be measured after

the initial breakaway torque required to loosen the nut from the output flange.

Each time the nut is removed, deeply scribe one of the flats on the nut. Thiswill allow service personnel to determine how many times the nut has been

used and prevent the nut from being used more than five times.

17. REBUILD/OVERHAUL INSTRUCTIONS

Refer to the current edition of Service Manual SM1314EN or SM1270EN for rebuild

or overhaul of the transmission.


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21. CHECKING FLYWHEEL (ENGINE-MOUNTED MODELS)

Check the 12-bolt circle at the front of the flywheel. The 12-20 threads mustbe undamaged, and the holes free of chips or foreign material.

Check the pilot boss (at center of flywheel) for damage or raised metal that

would prevent free entry into the flexplate hub adapter. Check the starter ring gear for excessive wear or damage. Check welds that

retain the ring gear (where applicable).

22. INSTALLING BRAKE AND OUTPUT FLANGE

Check the rear oil seal for failure or damage. For replacement instructions,refer to Service Manual SM1314EN or SM1270EN.

Lubricate the oil seal with oil-soluble grease.

Check the output flange or yoke for damage or wear. The oil seal contactsurface must be smooth and regular to prevent oil leaking past the rear oil

seal. Rotate the flange during installation to prevent seal lip damage.

Install the parking brake assembly. Tighten the bolts to the torquerecommended by the vehicle manufacturer.

Install the output flange or yoke. The brake drum, if it mounts ahead of thefl

ange or yoke, must be attached before thefl

ange is installed, and its boltstightened to the torque recommended by the vehicle manufacturer. Be sure the

flange or yoke hub is seated against the transmission rear bearing.

The output flange or yoke on straight-through model transmissions is retainedby a large self-locking nut. This nut may be reused up to five times if it meets

running torque requirements during removal.

Each time the nut is reused, deeply scribe one of the wrenching flats. This willallow the mechanic to determine how many times the nut has been used.

Check the output shaft and retaining nut threads to ensure that they are cleanand free of damage. To prevent thread galling and inaccurate torque during

nut installation, apply Molycote Type G or equivalent lubricant to the threads

of the output shaft and retaining nut.

Install the retaining nut and tighten to 600800 lb ft (8141084 Nm).

PREPARINGTRANSMISSION FOR

INSTALLATION

SECTION

II


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Dropbox models with manual disconnect output clutches use two bolts,shims, and a locking tab to retain the flange and retainer. Refer to Service

Manual SM1314EN or SM1270EN for shimming procedure and bolt torque.

If the brake drum mounts behind the flange or yoke, install the drum andretain it with bolts or nuts (as required). Tighten the bolts or nuts.

23. INSTALLING INPUT FLANGE (REMOTE-MOUNTED)

Check the front oil seal for failure or damage. For replacement instructions,refer to Service Manual SM1314EN or SM1270EN.

Lubricate the oil seal with oil-soluble grease.

Check the input flange or yoke for damage or wear. The oil seal contactsurface must be smooth and regular to prevent oil leaking past the front oil

seal. Rotate the flange during installation to avoid seal lip damage.

Install the input flange or yoke. Be sure it is seated against the bearing in thefront of the transmission front cover.

The input flange or yoke is retained by a large self-locking nut. This nut maybe reused up to five times if it meets running torque requirements during

removal.

Each time the nut is reused, deeply scribe one of the wrenching flats. This will

allow the mechanic to determine how many times the nut has been used. Check the input shaft and retaining nut threads to ensure that they are clean

and free of damage. To prevent thread galling and inaccurate torque during

nut installation, apply Molycote Type G or equivalent lubricant to the threads

of the input shaft and retaining nut.

Install the retaining nut and tighten to 450550 lb ft (610745 Nm).

24. INSTALLING RANGE SELECTOR LEVER

Loosen the clamp bolt in the splined range selector lever.

Locate the punch mark that was put on the outer side of the lever whenremoved.

Spread the clamp end of the lever, and install the lever so that the punch markaligns with the index mark on the end of the transmission selector shaft. Push

the lever onto the shaft until the splines fully engage.

Tighten the clamp bolt to retain the lever.

CAUTION: Do not drive or force the lever onto the shaft. Internal

damage to the transmission might result.


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25. INSTALLING PTO (APPLICABLE AT ANY LOCATION)

Space limitations will determine whether the PTO should be installed before or after

the transmission is installed.

The prescribed backlash between the drive gear (in transmission) and driven

gear (in PTO) is 0.0060.029 inch (0.150.73 mm) for the engine-driven andturbine-driven PTOs.

Establish the proper backlash by selecting the proper thickness shims

(gaskets) when mounting the PTO. To ensure proper installation, locate the PTO unit driven gear (prior to

installation) immediately behind the transmission drive gear. Install two

headless guide bolts into the top and bottom of the PTO pad. Install the PTO

unit.

Gear backlash can be measured through the inspection port provided in somePTO housings.

For a PTO mounted at either the top or side of the converter housing, theprescribed backlash is in addition to that already provided between the drive

gear in the transmission and its driving gear at the rear of the torque converter

pump. Thus, it is necessary to measure the drive gear/converter pump gear

backlash before installing the PTO.

On PTO assemblies that require pressure lubrication, install the lubricationtube and fittings. The lubricating oil comes from the line returning to the

transmission from the oil cooler. Oil should be directed to the PTO lubrication

circuit after passing through a 0.060 inch (1.52 mm) orifice. For the engine-

driven PTO, the maximum orifice size permitted is 0.110 inch (2.79 mm). For

the converter-driven PTO, the maximum restriction is 0.032 inch (0.81 mm).

This restriction is usually provided in the PTO.

26. INSTALLING SHIFT MODULATION CONTROLThe shift modulation control should be installed after the transmission is installed.

ReferenceParagraph 410.

CAUTION: Cork or other soft gaskets cannot be used to mount the

PTO. Use only shims or gaskets recommended by the PTO

manufacturer.

CAUTION: PTOs using transmission main pressure to apply the PTO

must have main pressure dead-headed at the valve when not in use.


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27. INSTALLING OIL FILLER TUBE

The oil filler tube may be installed before the transmission is installed into the

vehicle, unless its presence will interfere with transmission installation.

Install the oil filler tube onto the oil pan boss. If the tube is retained to the oil

pan by a nut, tighten the nut to 90100 lb ft (123135 Nm).

If the tube is retained by bolts, install oil filter tube and gasket onto the oilpan. Install two 516-24 bolts with lockwashers into the oil pan boss to retain

the tube assembly. Tighten the bolts to 1316 lb ft (1822 Nm).

Fasten the upper end of the oil filler tube with brackets and bolts as required toprevent cracks caused by excessive vibration.

Install the dropbox filler tube or oil level check tube into the dropbox (seeFigure 56).

CAUTION: Ensure that the proper length bolts are used. Using bolts

that are too long may cause cracks (leaks) in the pan.


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31. CHECKING FLEXPLATE DRIVE ASSEMBLY(TRANSMISSION ENGINE-MOUNTED)

Inspect the flexplate. Replace it if worn or damaged. Examine the flexplate forcracks, distortion, and elongated bolt holes.

Check the engine crankshaft end play. It must be within the limits prescribedby the engine manufacturer.

Install the plate assembly onto the engine crankshaft using the bolts andtorques prescribed by the engine or vehicle manufacturer. Refer toFigure 11

for proper position of installed flexplate.

Check the concentricity of the engine crankshaft hub with the flywheelhousing. Refer to engine specifications for runout limits.

32. CHECKING INPUT DRIVE COMPONENTS(TRANSMISSION REMOTE-MOUNTED)

Inspect the condition of the shaft. Tubular shaft must not be dented or bent.Welds must be sound.

Remove any accumulation of grease and dirt.

Inspect universal joints, yokes, coupling flanges, and slipjoint splines for wear

or damage. Lubricate universal joints and slipjoints. Use the vehicle manufacturer's

recommended lubricants.

Check universal joints or slipjoints for indexing to conform to vehiclemanufacturers specifications.

NOTE: Misindexing of the driveline can result in premature

transmission failure.

PREPARING VEHICLEFOR TRANSMISSION

INSTALLATION

SECTION

III


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33. CHECKING CHASSIS AND DRIVELINE

Inspect the chassis and driveline for the following and correct any faulty conditions:

Broken or worn transmission mounts.

Damaged or missing isolators (rubber mounts).

Improper or damaged bolts, hardware. Cross-frame members, rear-support members.

Front mounting spacers (some installations have spacers to adapt narrowconverter housing mounts to wider mountings on frame.

Driveline midship or hanger bearings.

Driveline yoke slipjoints for freedom of movement, wear, damage,lubrication, and indexing.

Universal joints for freedom of movement, wear, damage, and lubrication.

Auxiliary transmission or transfer case for mountings, alignment, flanges oryokes, backlash, and oil leaks.

PTO driven equipment, shafts, and couplings for condition and alignment.

34. OIL COOLER, OIL FILTER, AND LINES

Inspect condition of chassis and transmission-related plumbing. Correct any faulty

conditions found. Oil cooler (heat exchanger) clean and flush or replace if cleaning and

flushing are not satisfactory.

Oil cooler connecting lines clean and flush; inspect for deterioration, faultyconnector, kinks.

External oil filter replace filter element; inspect fittings, threads, mounting.

Oil filter lines clean and flush; inspect for deterioration, faulty connectors,kinks.

After a transmission failure that introduces debris into the oil system,complete cleanup of the system cannot be assured. Repeated cleaning and

flushing may not remove all debris from the oil cooler. Installation of an

auxiliary filter between the cooler and transmission (in return line) is

recommended for use in retarder and non-retarder transmissions. Refer to the

latest revision of Service Information Letter (SIL) 12-TR-93 for Allison

high-efficiency filter recommendations.


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35. CHECKING CONTROLS

Inspect condition of transmission control components on vehicle. Correct any faulty

conditions found.

Range selector control for freedom of movement, frayed or kinked cables,

lubrication, worn rod ends and clevis pins, cotter pins, loose parts, damagedthreads, and proper routing.

Mechanical modulator control components for freedom of movement, frayedor kinked cables, lubrication, worn rod ends and clevis pins, cotter pins,

damaged threads, and proper routing.

Parking brake control for cracks, bends, wear, damaged threads, worn rodends and clevis pins, cotter pins, and proper operation.

PTO controls for damage, wear, lubrication, and proper operation.

Hydraulic retarder control for damage, wear, frayed or kinked cable, worn rodends and clevis pins, cotter pins, lubrication, and proper operation. When

control is connected to the hydraulic retarder control valve, the valve must

have full travel of 112inch (38 mm) from ON to OFF positions.

Speedometer drive cable for wear, damage, kinks, lubrications, and properrouting.

Wiring and related electrical components of signals, solenoids valves and

pilot valves, sensors or switches for poor connections, frayed wiring, anddamage.

Capillary tubes or sensors for temperature gauges.

Oil pressure gauge tubing for damage, kinks, and proper routing.


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41. HANDLING

Handle the transmission carefully to prevent damaging the transmission andcomponents.

Use a hoist or transmission jack of a type that permits precise control of

transmission movements during installation.

42. MOUNTING TO ENGINE (TRANSMISSION ENGINE-MOUNTED)

Align one of the twelve bolt holes in the flexplate with the access opening atthe front of the engine flywheel housing.

Install a headless 12-20 guide bolt into one of the tapped holes in theflywheel. Align the guide bolt with the flexplate hole at the access opening.

Lubricate the pilot boss at the center of the flywheel with molybdenumdisulfide grease (Molycote G or equivalent).

Move the transmission toward the engine while guiding the pilot boss on theflywheel into the flexplate hub (adapter) and the guide bolt into the hole in the

flexplate.

Seat the transmission squarely against the engine flywheel housing. NO forceis required. If interference is encountered, move the transmission away from

the engine and investigate the cause.

Align the bolt holes in the converter housing with those in the engine flywheelhousing. Install all of the bolts, finger tight, that retain the transmission to the

engine.

Tighten four bolts at 90 degree intervals around the converter housing boltcircle. Then tighten the remaining bolts. Use the torque recommended by the

vehicle or engine manufacturer.

CAUTION: The converter housing must be flush against the engine

flywheel housing before tightening any bolts. Do not use the bolts to

seat the housing.

INSTALLINGTRANSMISSION INTO

VEHICLE

SECTION

IV


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Remove the guide bolt through the access opening in the engine flywheelhousing. Replace it with a 12-20 x 1 inch self-locking bolt. Tighten the bolt

finger tight at this time.

While rotating the engine, install the eleven remaining, 12-20 x 1 inchself-locking bolts into the flywheel, finger tight. When all bolts are in place,

tighten them to 96115 lb ft (130156 Nm).

Install the flywheel housing access cover.

43. INSTALLING TRANSMISSION MOUNTING COMPONENTS

Install all bolts, washers, spacers, isolators, supports or cross membersrequired to support the transmission in the vehicle frame.

Tighten the bolts to the torque recommended by the vehicle manufacturer.

44. REAR SUPPORT OF THE CLBT 750DB

Do not support the rear of the transmission by using the two 4-bolt side

mounting pads of the first clutch and adapter housing assembly. These padsare to be used for rear support in straight-through models only. When

installing the dropbox model (CLBT 750), the transfer gear and bearing

retainer side pads should be used for rear support. These mounting pads are

cast iron and have six 34-10UNC tapped holes(Figure 41).

NOTE: Do not tighten any flywheel bolts until all of the bolts have

been installed and tightened finger tight.

CAUTION: Use the type and grade of mounting bolts recommended

by the vehicle manufacturer. The 58-11 bolts in the converter

housing must have at least 114inch (32 mm) thread engagement. The34-10 bolts in the rear adapter housing must have at least 112inch

(38 mm) thread engagement but must not bottom in the adapter

housing.


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Figure 41. Rear Support of the CLT, CLBT 750

45. COUPLING TO ENGINE (TRANSMISSION REMOTE-MOUNTED)

Install (if removed) the input drive shaft components that connect the engineand transmission.

Couple thefl

ange or yoke to thefl

ange or yoke at the front of thetransmission. Use the bolts and torque recommended by the vehicle

manufacturer.

Check the alignment of the transmission with the engine against the vehiclemanufacturer's specifications.

46. COUPLING TO DRIVELINE

Couple the driveline companionfl

ange or universal joint yoke to thefl

ange oryoke on the transmission. Use the bolts and torque recommended by the

vehicle manufacturer.

Check the universal joint angularity (all joints in driveline) to determine ifthey are within the specifications of the vehicle manufacturer.

V06543

The 4-bolt pad on the first clutch adapterhousing is used when mounting a straight thrumodel, but should not be used for rear support

of the CLT, CLBT 750 DB

The 6-bolt pad on the transfer gear housingand bearing retainer should be used for rear

support of the CLT, CLBT 750 DB


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14

47. CONNECTING COOLER AND OIL FILTER LINES

Figures 42 through46 illustrates the different oil filter and oil cooler connections

required for engine-driven PTO converter housings with no retarder; engine-driven

PTO with retarder; no engine-driven PTO or retarder; or no engine-driven PTO with

retarder.

On CLBT 750 models, be sure that the plugs closing certain oil andtemperature bulb openings are installed and tightened. Tighten plugs

in oil ports to 4050 lb ft (5468 Nm). Tighten plugs in the

temperature sensor port to 1620 lb ft (2227 Nm). The hexagon-head

plugs seat on O-ring seals.

Be sure oil lines are the proper size and type recommended. Use new O-ringseals where required.

Connect the oil lines to the transmission and to the oil cooler and external oilfilter. Check to see that the lines are clean and unobstructed.

The lines should be tightened in the transmission to 4050 lb ft (5468 Nm).

Check for sharp bends, kinks, twists, and contact with components that willchafe the oil lines.

Check for proximity to manifolds or exhaust pipes. Excessive heat will hasten

the deterioration of oil lines. Recheck the routing of all lines with the applicable illustration(Figures 42,

43, 44, 45, and46).

Figure 42. Early CLBT 750 Without Engine-Driven PTO

PLUG

ENGINE TO FILTERINPUTRETARDERHOUSING

FROMCOOLER

FROM FILTER

TO COOLER(CONVERTER-OUT

TEMPERATURE BULBADJACENT)

ENGINE

PLUG

CONVERTERHOUSING

LEFT SIDE RIGHT SIDE V02378.01


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15

Figure 43. CLT 750 With Engine-Driven PTO

Figure 44. CLT 750 Without Engine-Driven PTO

Figure 45. Current CLBT 750 Without Engine-Driven PTO

ENGINE

PTO MOUNT

TO FILTER

FROM FILTER

CONVERTER-OUTTEMPERATURE BULB

TO COOLER

FROM COOLER ENGINE

V02388LEFT SIDE RIGHT SIDE

ENGINE 2-BOLT COVER

TO FILTER

FROM FILTER


TO COOLER

FROM COOLER ENGINE

V02380LEFT SIDE RIGHT SIDE

2-BOLT COVERENGINE

FROMCOOLER

TOCOOLER

FROM FILTER


PLUG (EARLIER MODELS)ENGINE

PLUG

V02379

TO FILTER

RIGHT SIDELEFT SIDE


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16

Figure 46. CLBT 750 With Engine-Driven PTO

48. CONNECTING RANGE SELECTOR CONTROL

Place the operators range selector control at the N(Neutral) position. Placethe transmission selector lever at the neutral position (first detent clockwise

from stop at extreme counterclockwise position when lever is installed to

point downward). Mannesmann Rexroth Shifter (formerly American Standard WABCO)

1. Place the Mannesmann Rexroth cylinder in the neutral position(Figure 82).

2. Adjust the linkage as necessary to correspond to transmission range

selector detents.

3. In fourth range the T bar should be horizontal with the oil pan.

Bennett Shifter

1. Two people will be required to connect the linkage for the range selector.

2. Place the Bennett shifter in the neutral position. The neutral position for

the Bennett shifter used with the CLBT 750 is achieved by moving the

shaft of the shifter(Figure 86) into its bore until fully seated, then

extending the shaft one position.

3. Adjust linkage to correspond to the transmission range selector.

NOTE: While adjusting the linkage to correspond to a particular

range, air must be continuously supplied to the Bennett shifter. If air isnot supplied continuously, the shaft will extend to make a shift. When

the air is released, the shaft will once again become free to move

allowing the linkage to be adjusted improperly.

ENGINE ENGINE

TO FILTER

PLUG

FROMCOOLER

TOCOOLER

INPUT RETARDER HOUSING


CONVERTERHOUSING

PLUG PLUG

V02390

FROM FILTER

LEFT SIDE RIGHT SIDE


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17

After verifying that the shifter detents correspond to the transmission rangeselector detents, return the selector to neutral.

Find the neutral position for the governor step valve body(Figure 61).

Connect and adjust the governor step valve body linkage as necessary tocorrespond to the transmission range selector detents.

Shift through all selector positions, checking each to ensure that the valvebody detents correspond to respective selector positions.

49. CONNECTING HYDRAULIC RETARDER CONTROL(CLBT MODELS)

Place the operators control at the OFF (disengaged) position.

Check the hydraulic retarder control valve. The valve is spring loaded to retractinto the valve body when the retarder is OFF. Lift the valve upward, to ONposition, to check for full travel of 112inch (38 mm) from OFF to ON position.

Release the valve, permitting the spring to retract the valve.

Adjust the linkage so that rod end or clevis registers with the pin hole in theretarder valve. Connect the linkage to the retarder valve and check the

operation of the valve. The valve must be fully extended when the operators

control is at ON; the valve must be fully retracted when the control is at OFF.

In all installations the control system must include a return spring to ensurepositive release of the retarder valve when the pedal or lever is at the released

position.

410. CONNECTING MODULATOR CONTROL

Install the modulator actuator rod into the modulator valve body through themodulator mounting hole in the transmission housing(Figure 47).Later

models incorporate a retained actuator rod, installed during assembly of thevalve body.

Figure 47. Location of Modulator, Neutral Start Switch, and Selector Shaft

NEUTRAL STARTSWITCH LOCATION

SELECTORLEVER SHAFT

V06585

MODULATORACTUATOR ROD(LATER MODELSRETAINED INTERNALLY)


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18

Connect the engine (throttle) end of the modulator cable housing to itsmounting.

Four types of modulators are currently available for use; a mechanical pushtype, a mechanical pull type, air, and electric. The following steps should be

used to determine which type of mechanical modulator is required and how to

adjust the modulator cable travel.

Open the engine throttle fully and check whether the throttle linkage will push

or pull(Figure 48) the cable core when the throttle linkage is moving towardfull-throttle position. If it will push the cable core, then push the cable core

until it reaches the end of its travel. If movement of the throttle linkage toward

full-throttle position will pull the cable, then pull the cable to the end of its

travel.

Figure 48. Current Mechanical Modulators

Adjust the clevis or rod end of the cable core until it registers with the hole inthe throttle linkage lever, and the connecting pin can be freely inserted. With

the pin removed, rotate the clevis or rod end one additional turn

counterclockwise (viewing cable core from its end) for pull-type arrangement,

or one additional turn clockwise for push-type arrangement. This ensures that

the modulator does not prevent the throttle lever from reaching the full on

position. Install the clevis pin or rod end to connect the throttle linkage and

cable. Tighten the lock nut against the clevis or rod end.

Check the travel of the cable core when the throttle is moved from fully opento fully closed position. The system is designed to provide a minimum travel

of 1.187 inch (30.15 mm), and a maximum of 1.56 inch (39.6 mm). However,

cable travel may vary for different modulator manufacturers.

NOTE: If the modulator actuator rod is omitted or on earlier models,

falls into the pan during modulator installation, the result will be

excessive modulator pressure which will cause the lockup clutch toengage and kill the engine.

PUSH TYPEPULL TYPEV02396


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19

Various kinds of modulator controls may be used, but the object of each is toapply increasing force to the modulator actuator rod as the engine fuel control

is moved from closed to open position. The most common type of control is

the cable-operated mechanical actuator with either a lever or sliding wedge to

vary the force on the modulator valve. Both of these types are convertible to

use either push or pull force on the cable when the throttle is opened. Makesure the modulator control, when connected to the throttle linkage, provides

an increasing force against the modulator actuator rod in the transmission

when the engine throttle is moved toward the open throttle position.

Current actuators include a lever that is marked PUSH on one side, and PULLon the opposite side. When the modulator control cover is removed, the word

PUSH or PULL can be seen and will indicate how the device is assembled

(seeFigure 48).

Earlier mechanical actuators include a sliding wedge (cam). When the coveris removed, the position of the wedge can be seen. When the smaller end of

the wedge is toward the cable housing, the device is the pull type; when the

larger end of the wedge is toward the cable housing, the device is the push

type (seeFigure 49).

The conversion of either the lever or wedge type to the opposite mode ofoperation is only a matter of reassembling the internal parts. Reverse the

positions of the lever, spring, and thimble in the lever type to convert it;

reverse the wedge in the wedge type. Be sure the modulator control action is as required.

Install the O-ring seal onto the modulator control. Coat the O-ring withoil-soluble grease.

Install the modulator control into the transmission. Retain the control housingwith the spring clip and the 516-18 x 34inch bolt provided. The convex side of

the formed end of the clip must be toward the transmission and against the

shoulder of the actuator stem. Tighten the bolt to 1316 lb ft (1822 Nm).

Check the cable routing. Bends must not be less than 8 inch (203 mm) radius.The cable should not be nearer than 6 inch (152 mm) to the engine exhaust

pipe or manifold. The cable must follow the movements of the throttle

linkage. It may be necessary to add a spring to ensure that the movement

occurs smoothly.

Adjust other types of modulator controls as recommended by the vehiclemanufacturer.


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20

Figure 49. Old Style Mechanical Modulator

411. CONNECTING POWER TAKEOFF CONTROLS

If not previously installed, mount the PTO onto the transmission. Refer toParagraph 25 for instructions.

Connect controls to the PTO. Check for proper operation of the controls.

Check for cable or linkage rod routing. Kinks, sharp bends, and proximity ofthe cable to exhaust pipes or manifold must be avoided. Rods or linkage must

not rub or interfere with adjacent parts.

Couple the PTO output to its driven equipment. Check couplings or universaljoints for proper assembly and alignment.

CAUTION: PTOs using main transmission pressure to apply the PTO

must have main pressure dead headed at the valve when not in use.

SNAPRING

PLUNGER

CAM (WEDGE)

PULL-TO-OPERATE ILLUSTRATED

CONTROLCABLE

SPRING

SEAT

L02397

5.5in

.MID

TRAVEL

(140

mm)

LENGTH

AS

REQUIRED

1.5 in. (38 mm)TRAVEL


28/64

21

412. CONNECTING PARKING BRAKE CONTROLS

Connect and properly adjust the parking brake linkage.

Adjust the brake shoe-to-drum clearance, or disc brake pads as specified bythe manufacturer.

413. CONNECTING OUTPUT DISCONNECT CONTROLS(DROPBOX MODELS ONLY)

Connect and properly adjust the output disconnect linkage. Refer to thevehicle manual.

414. CONNECTING SPEEDOMETER DRIVE

Install the speedometer driven gear assembly into the transmission. Tightenthe body in the transmission rear cover to 4550 lb ft (6168 Nm). If no

speedometer drive is provided, be sure the plug is installed to close the hole in

the housing (torque is the same as for the driven gear body).

Install the speedometer drive cable onto the driven gear assembly. Tighten thenut to 50 lb in. (5.65 Nm). Avoid kinks or sharp bends in the cable assembly.

All bends must have a radius of 6 inches (152 mm) or more. No more than

one 90 degree bend is allowed.

415. INSTALLING TEMPERATURE AND PRESSURE SENSORS ANDELECTRICAL COMPONENTS

Install temperature sensors (capillary tube and bulb or thermocouple) into theconverter housing or hydraulic retarder valve.

SeeFigures 42 through46 for various locations. Tighten the 12inch pipe

thread adapter sufficiently to prevent leakage. Install the bulb into the adapter and tighten the nut into the adapter.

Check the capillary tube for interference with parts that might chafe ordamage the tube. Long tubes may require clips or brackets for support.

Install electrical temperature sensors into the proper openings(Figures 42through46). Connect electrical leads to the sensors.

Check that all openings in CLBT models that require plugs are plugged(Figures 42 through46).

Install the neutral start switch (if so equipped) into the opening in the left sideof the transmission housing(Figure 47). The switch must include an

aluminum washer (gasket) approximately 0.090 inch (2.29 mm) thick. Apply


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22

pipe sealant (Loctitewith Teflonor equivalent) to the threads of the switch.

Tighten the switch to 5060 lb ft (6881 Nm).

If the neutral start switch is not mounted at this location, the opening must beplugged.

Connect the wire leads that serve the neutral start switch.

If so equipped, install the reverse signal switch at the right side of thetransmission housing. Tighten the switch to 45 lb ft (5.46.8 Nm). Connect

the electrical leads.

Install and connect other electrical components such as heaters, winterizationequipment, and pressure sensors.

Install the pressure gauge tubes if so equipped.

Check the starting circuit. The starter should operate only when thetransmission range selector is at the neutral position.

416. FILLING THE OIL SYSTEM

Be sure the oil system is properly filled before starting the engine. Refer toSection V, OIL SYSTEM.

NOTE:The type and location of the neutral-start switch is optional.

Provision is made for installation on the transmission(Figure 47),if

desired.


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23

51. FILLING THE SYSTEM

After the overhaul or rebuild, the system, including all external plumbing andcomponents such as filters and heat exchanger, must be refilled.

The initial running of the engine after overhaul will cause a rapid draw-down

of the transmission oil level. Check the oil level several times during the firstfew minutes of operation and add oil as needed to maintain the level within

the COLD RUN band.

Make an accurate check after the level has stabilized and the oil is hot(160200F; 7193C). Refer to the following paragraphs in this section for

oil system data.

52. DEEP OIL PAN

An 812inch deep cast iron oil pan is standard on the CLBT 750 transmission.This oil pan increases the sump oil capacity to provide a better roadability in

on-highway and/or off-highway operations and increased pan durability in off

highway operation. The increased oil volume (approximately 3 quarts

(2.8 liters)) maintains a more consistent oil level thereby ensuring ample oil

supply for transmission operation and cooling.

53. OIL PAN INTERCHANGEABILITY

Oil pan parts are fully interchangeable on transmissions in field service but, all oil

pan parts for a chosen depth must be used together. See Parts Catalog to obtain

correct parts.

Figure 51 illustrates the dimensions relative to the various pan dimensions. A review

of vehicle installation will determine clearances necessary for installation of the

heavy duty deep oil pan.

The oil fill tube used on the 6 inch pan can be adapted to the deep pan with no

change. Dipstick markings are illustrated inFigure 54.Figures 52 and53

illustrate oil levels on transmissions equipped with the 6, 7, and 812inch oil pan.

OIL SYSTEMSECTION

V


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Figure 51. Six Inch and Eight and One-Half Inch Oil Pans

54. SPARE PARTS INFORMATION

All old parts will be maintained for servicing straight-through model transmissions in

field service prior to the effective serial number and current dropbox model

transmissions incorporating the various oil pan options.

Two-bolt flange forcustomer furnishedfill tube and dipstick

Two-bolt flange forcustomer furnishedfill tube and dipstick

1.000 NPTF(for heating

element)

STANDARD OIL PAN812inch deep

6 inch OIL PAN

1.000 NPTF(for drain and

heating element)

NOTE: Dimensions are in inches (millimeters)

0.29(7.4)

22

7.035

(178.7)

6.437

(163.5)

33

6.578(167.07)

5.978(151.83)

3

2

2

18.08(459.2)

8.895(225.9)

8.329(211.56)

1.28(32.5)

R

20.71(526.1)

25.78(654.7)

18.100(459.75)

21.360(542.55)

25.670(652.02)

12.83(325.8) 17.26

(438.3)

13.89(354.5)

14.48(368.4)

16.61(421.8)

13.205(335.41)

13.465(342.01)

14.705(373.51)

17.26(438.3)

V06544


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Figure 52. Transmission Oil Levels (6 inch Deep Pan)

Figure 53. Transmission Oil Levels (7 and 812 inch Deep Pan)

55. INSTALLATION OF 812INCH TRANSMISSION OIL PANASSEMBLY AND OIL FILLER TUBE

All oil pan assemblies and related parts are installed in the same manner, with the

following assembly exceptions.

Tube assembly P/N 6884063 is installed at the same location, however, it issecured by a mounting bolt of the lockup clutch cutoff valve body assembly

and the main valve body assembly.

The 812inch oil pan filter is retained to the valve body by three14-20 x 314 inch bolts.

3.75 in.*(95.2 mm) HOT RUNBAND160200F(7193C)

OIL PAN

FILL TUBE HOLECOLD RUN BAND60120F (1649C)

TOP OFOIL PAN

V02371.01

3.00 in.*

(76.2 mm) 4.81 in.(122.2 mm)

2.50 in.(63.5 mm)

1.50 in.(38.1 mm)

* Approximate dimension. OEM/customer to establish cold run band at installation.

3.50 in.(89.9 mm)

2.50 in.

(63.5 mm)

4.75 in.*(120.6 mm)

COLD RUN BAND60120F (1649C)FILL TUBE HOLE

TOP OFOIL PAN

FULLADD

V02372.01

HOT RUN BAND160200F (7193C)

Difference between full and add levels is 2 U.S. quarts (1.9 liters)

* Approximate dimension. OEM/customer to establish cold run band at installation.


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The 812inch pan oil drain plug and washer are installed at the rear of the oilpan(Figure 51).

The same oil filler tube can be adapted for use with the 812 inch deep oil pan.

56. OIL LEVEL AND OIL DIPSTICK

Figure 53illustrates the oil levels relative to the 7 and 812inch oil pan. These oil

levels are referenced from the top of the oil pan or the pan to transmission housing

splitline.

The COLD RUN band level,Figure 54, is an approximate dimension to be

established by the OEM/customer at installation. An exact HOT RUN band

dimension and oil level should be established prior to the COLD RUN dimension and

oil level. A HOT RUN check for proper operating oil level is required.

Figure 54. Dipstick Markings Location

3.75*

(95.2)HOT

RUN

3.00*(76.2)

2.50(63.5)

1.50(38.1)

COLD

RUN

V06545

HOT

RUN

CHECK

INN

EUTR

AL

ATIDLE

4.75*(120.6)

3.50

(88.9)

2.50(63.5)

COLD

RUN

PROCEDURE:Use hot run band for 160200F (7193C)Use cold run band for 60120F (1649C)

NOTE:This illustration is not a template.Placement of the markings will varyaccording to the angle of thedipstick protruding into the fluid.Dimensions shown are in thevertical plane.

*Approximate dimension. OEM/Customerto establish cold run band at installation.

WITH 7 in. and 812 in.(177.8 mm and 215.4 mm)

DEPTH PAN

WITH 6 in. (152.4 mm)DEPTH PAN


TRANSMISSION-TO-OIL PAN SPLITLINE(TOP OF OIL PAN)


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To calibrate the new dipstick, strike a mark on the side of the oil filler tube (that has

been installed) to correspond with the top of transmission oil pan, referenced in

Figure 54. Position new dipstick down along the outside of oil fill tube, holding the

top even with the top of fill tube (where it would rest if installed into tube). Follow

contour of fill tube with the dipstick down to the mark previously scribed on side of

fill tube representing top of oil pan mark dipstick. Now, measure down 2.5 inch(64 mm) below this mark and scribe a line across dipstick, this will be the top line of

the HOT RUN band as illustrated inFigure 53.At a point 1.0 inch (25 mm) below

this scribed line, scribe another line across the dipstick; this represents the bottom of

HOT RUN and the top of the COLD RUN band. Measure down 1.25 inch (32 mm)

and scribe the bottom line for the COLD RUN band.

The oil capacity (initial full) of the 6 or 7 inch deep oil pan is 814U.S. gallons

(31 liters). The oil capacity (initial fill) of the 812inch heavy duty deep oil pan is

912U.S. gallons (36 liters).

57. CHECKING TRANSMISSION OIL LEVEL

Cold Oil Check (COLD RUN band). A cold oil check should be performedwith the engine idling and the oil temperature at 60120F (1649C). Oil

registering in the COLD RUN band indicates a sufficient quantity of oil to

safely operate the transmission until the temperature reaches 160200F

(71 93C). When the temperature is 160200F (7193C), a hot oil checkmust be made.

Hot Oil Check (HOT RUN band). After the temperature reaches 160200F(7193C), remove the dipstick from the oil filler tube and check the oil level.

If the oil level registers in the HOT RUN band(Figure 54), the oil level is

satisfactory for the operation of the vehicle. If the oil level registers on, or

below the bottom of the HOT RUN band, add oil to bring the oil level up to

the middle of the HOT RUN band.

Always check the oil level on the dipstick at least twice. Consistency isimportant in maintaining accuracy. If inconsistent readings persists, check the

transmission breather for dirt and obstructions. Improper venting atmosphere

may cause pressure buildups inside the transmission.

CAUTION: The oil level rises as sump temperature increases.

Therefore, do not fill above the COLD RUN band before the

transmission has reached normal operating temperature. Excessive oil

causes overheating and irregular shift patterns.


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58. OIL SPECIFICATIONS

Recommended oil specification is Allison-approved C-4. Usage should comply to the

information and chart related onFigure 55, relative to ambient temperature, fluid

viscosity grade, and preheat.

59. OIL CHANGE AND FILTER REPLACEMENT

Oil change and filter replacement frequency is determined by the transmissionapplication and the severity of operating conditions.

In general, the oil should be changed after 1,200 hours of operation. Theexternal filter elements should be changed every 600 hours of operation.

Severe operating conditions may require more frequent changes.

The internal suction screen does not require routine servicing. Do not removethe pan.

To drain the oil, remove the drain plug at the rear of the oil pan. The oil will

drain better if the transmission is hot. Replace the plug when the oil pan isthoroughly drained.

Remove the external oil filter element(s) and sealrings. Install a newelement(s) and new sealrings.

Four 24 U.S. quarts (22.7 liters) of Allison-approved C-4 oil into thetransmission. Check the oil level as outlined earlier in this section.

Figure 55. Fluid Viscosity Versus Ambient Temperature

CAUTION: The 30F (34C) sump temperature specification is

based on cold engine operation. Even if the engine is warm and capable

of full throttle output, the transmission should not be operated for

30 seconds to allow for buildup of sufficient main pressure.

AMBIENT TEMPERATURE F (C)

0W-20

30(34)

20(29)

10(23)

0(18)

10(12)

20(7)

30(1)

40 50

15W-40

30

40

10W 10-10W

FLUID

VISCOSITY

GRADE

V06546


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510. OIL OPERATING TEMPERATURES

The maximum oil temperature (converter-out temperature) during converter

operation is 300F (149C). The only exception to this limit is transmissions equipped

with input retarders. For intermittent retarder operation, the converter-out oil

temperature may exceed 275F (135C) but under no condition is the converter-out

oil temperature to exceed 330F (165C). If the maximum converter-out oil

temperature is reached, the following procedure should be followed:

Stop the vehicle and shift the transmission into neutral and operate the engineat 1500 rpm to reduce the transmission oil temperature.

If the transmission oil does not cool in approximately 30 seconds, or if itcontinues to overheat after operation is continued, stop vehicle and engine and

locate the problem.

Some confusion may exist concerning oil temperature and if the temperature quoted

is sump temperature or converter out operating temperature. The following chart

should eliminate the confusion:

511. OIL LEVEL FOR TRANSFER GEAR HOUSING (DROPBOX)

The oil level for the CL(B)T 750 dropbox has been changed. Excessive dropbox oil

temperature may result in some installations during continuous high speed operation.

Lowering the oil level will reduce these temperatures. The new, lower levels are asfollows:

The new FULL and ADD levels correspond to approximately 2.6 quarts (2.5 liters)

and 2 quarts (1.9 liters), respectively. With these reduced volumes, the ADD andFULL levels remain the same for a cold fluid level check or a hot fluid level check.

The oil used in the dropbox continues to be Allison-approved C-4, Grade 30.

Converter-Out Sump

Converter Operation 300F (149C) max 250F (121C) max

Retarder Operation 330F (165C) max 250F (121C) max

Lockup Operation 250F (121C) max 250F (121C) max

Normal Operating Temperature 160220F (71104C)

Minimum Sump Oil Temperature 150F (66C)

Distance From Lower Output Shaft Centerline

New Level Old Level

FULL 1.75 inch (44.45 mm) Below 0.5 inch (12.7 mm) Above

ADD 2.80 inch (71.12 mm) Below 0.5 inch (12.7 mm) Below

NOTE: Quantities may vary according to output configuration

options on the dropbox.


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Be sure oil level dipsticks are calibrated to correspond with the new FULL and ADD

oil levels(Figure 56).

Figure 56 illustrates an alternate fill pipe configuration that is recommended for the

dropbox. This configuration assures that the box will not be overfilled and provides

for a quick check of the actual level. A dipstick is not required with this configuration

nor is venting required. Basically, this configuration consists of nipples, elbow and

compression plug (or a threaded cap) with the end of the open fitting corresponding

to the FULL oil level requirement in the dropbox.

Figure 56. Dropbox Oil Level Indicator

V02375.01

FLUIDDRAINPLUG

FILL PIPE AND

LEVEL INDICATOR

34-14 NPTF

2 in.(51 mm)

FULL

3 in.(76 mm)

ADD

OUTPUT SHAFTCL


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31

61. GENERAL DESCRIPTION

The manual shift mode allows upshifts to be made regardless of transmission output

speed and prevents automatic downshifts. In addition to the powershift mode, the

normal automatic operation is maintained so that either manual or automatic shifting

can be selected for installations where the transmission serves a dual purpose.Switching from manual to automatic is achieved by an externally mounted customer

supplied two position valve* (mode shift valve) that controls the supply of oil to an

externally mounted valve body. Typical installations that would require this system

use the transmission in the power train for roading the equipment and to power some

working machinery located on the vehicle when it is stationary. Examples of

equipment of this type include: oil well servicing rigs, pumping and fracturing rigs,

oil well logging equipment, and logging trucks. In these dual purpose applications,

roading of the vehicle is permitted in automatic mode only. To achieve this

requirement, some type of interlock feature must be incorporated on the vehicle that

prevents the operator from selecting the manual mode when the vehicle is being

roaded. The following describes the complete installation of the kit.

* This valve mustbe selected from the following specified part numbers:

All above valves are used with subplate: DGMS-2-4E-10-S.

The above mode selection valves are recommended on the basis of satisfactory field

experience. These mode selection valves are also used with other manual/automatic

shift systems. Since these are four-way valves, one port must be blocked to create the

three-port function defined in SIL 29-TR-82.

Part Description Part Number Source

Solenoid-piloted: DG4V-3S-2A-M-FW-B5-60 Eaton Corporation

Hydraulics Operations

15151 Highway 5Eden Prairie, MN 55344

Phone: 888-258-0222

Air-piloted: DG-18V-3-2A-P-60

Hydraulic-piloted: DG3V-3-2A-7-S-60

Manual: DG17V-3-2N-60

Air-piloted: Lex-Air BP2S-38NPT Eagle Equipment

245 Industrial Drive

Franklin, OH 45005

Phone: (513) 382-1691Fax: 513-746-1656

Type 1 with VitonSeals

DUAL MODEOPERATION

SECTION

VI


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32

Spacer.This is not included in kit, but it is required with the installation of the check

valve on dropbox models prior to Serial No. 24218. ReferenceFigure 62.

62. FUNCTIONAL OPERATION

The kit consists of the external valve body as shown inFigure 61 and a check valveassembly P/N 6882811 shown inFigure 62.

Manual Mode.Oil is supplied to the valve body from the filter out line. A priority

valve in the valve body directs this oil first to the mode shift valve (LINE 1) and

secondly to the main return line to complete the normal filter circuit. During manual

operation the modeshift valve directs the supply of oil back to the valve body (LINE

2) to feed the selector valve. The selector valve, which is mechanically linked to

transmission lever, in turn feeds oil to a multi-level regulator which produces five

different constant levels of oil pressure according to position of the selector. These

pressures are: Rev, N, 1st 0 psi; 2nd A psi; 3rd B psi; 4th C psi; 5th D psi

as shown in Figure 61. These various levels of pressure may differ according to the

transmission valve body calibration with which it is used. The output from the step

regulator is then fed to the rear cover (LINE 3) where it intersects the governor output

line through the double ended check valve provided in the kit. When the pressure

from the external valve body exceeds the pressure from the governor, the ball seats in

the upward position and oil passes out the side of the check valve to the shift valves in

the transmission valve body. When the supply to the manual valve body is turned off,the governor pressure from the transmission governor seats the ball in the downward

position and transmission operates as an automatic. When the feed to the manual

valve body is on and the output of the transmission governor exceeds the output of

the external valve body, the ball will be seated in the down position and the

transmission will be in the range corresponding to that governor pressure. In this way,

the transmission governor overrides the step governor and thereby provides a high

speed downshift inhibiting feature.

Automatic Mode.The mode shift valve blocks the flow of oil from the priority valve

(LINE 1) and exhausts the governor feed (LINES 2 and 3) back to the transmission

sump (LINE 4). The check valve now seats at the bottom end of the valve and the

transmission governor supplies oil to the control valve body producing normal

automatic operation.

63. INSTALLATION

No rework is required on transmissions S/N 4398 and later for check valveP/N 6882811. Prior to 4398, a rework as shown inFigure 62 is required to accept

the 6882811 check valve. All hydraulic connections are external and provided by the

customer. SAE 100 R5 specification hose is satisfactory.

An additional spacer is required on dropbox models, prior to transmission S/N 24218.


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33

Figure 61. Externally-Mounted Valve Body

Use only ondownshift inhibitdefeat optionSection 64

MAIN FEED TOGOVERNOR

(DROPBOX ADAPTERHOUSING)TO GOVERNOR

(REAR COVER)

PRESSURECODE psi kPa

0

2329

5258

8995

147157

or Main

0

159200

359400

614655

10141083

or Main

0

A

B

C

D

V06547

MANUALGOVERNORPRESSURE

MAINRETURN

FILTER OUT

LINE 2

D

C

B

A

12

3

4

5

N

R

R N 5 4 3 2 1

LINE5

LINE4

LINE3

MODESHIFT

VALVE

LINE 1


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34

Figure 62. Check Valve Installation

If desired, special modification to the CL(B)T 750, 2100, and 2300 rpm dropbox

models can be performed to defeat the downshift inhibiting feature in the manual

mode only. Refer toDOWNSHIFT INHIBITING CL(B)T 750, 2100, AND 2300

RPM DROPBOX MODELS ONLY.

The valve body has six holes for mounting purposes and can be mounted on the

transmission or on the vehicle. Since the valve body selector valve and thetransmission selector lever are mechanically linked, relative motion between the

transmission and frame that would cause a change in their relative position cannot be

allowed to exist.

Transmissions prior to S/N 4398ream hole in rear cover 0.34100.3420 in.(8.6618.667 mm) DIA x 1.48 in. (37.6 mm)deep minimum

SPACER(Use only on dropbox modelsprior to S/N 24218)

V06548

CHECK VALVEP/N 6882811

From external

valve body


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35

A necessary requirement of the installation is that vehicle roading be done in

automatic mode. To achieve this, some form of interlock is necessary with the signal

that actuates the mode shift valve. This could come from an engagement mechanism

in the vehicle power train or a signal that activates the shift controller in the cab.

Either manual or automatic operation is permissible for no-roading operation.

Drainbacks to the sump (LINES 4 and 5) can be fed into the PTO cover, dipstick

tube, or the drain plug in the transmission oil pan.

64. DOWNSHIFT INHIBITING CL(B)T 750 (2100 AND 2300 RPMDROPBOX MODELS ONLY)

The downshift inhibiting feature can be defeated in the manual mode only, if desired.

Thus, a downshift will be allowed to occur regardless of transmission output speed. It

is important that this modification be restricted to manual/automatic installations

where there are very small output inertias in the working mode. Applications

satisfying this requirement are primary oil well pumping rigs and other

miscellaneous pumping applications.

The dropbox adapter housing was modified effective transmission S/N 27267 to

accept a customer supplied sleeve 0.340/0.339 OD x 0.185/0.277 ID x 2.01/1.99 inch

long (8.636/8.611 x 4.70/7.04 x 50.8/50.5 mm). Refer toFigure 63. On

transmissions prior to S/N 27267, it is necessary to rework the inside governor

pressure tap (main oil feed to the governor) to accept the sleeve (refer toFigure 62).

Since this operation requires partial disassembly of the transmission, this operation

should be performed by an authorized Allison Transmission repair outlet.

Figure 63. Downshift Inhibit Sleeve

The function of the sleeve is to block an internal main oil feed hole to the governor,

allowing main oil to be fed to the governor through an external line from the mode

shift valve in the automatic mode and to exhaust any governor pressure in the manual

mode.

CAUTION: Dual mode circuitry is not to be tapped for use elsewhere

in the transmission.


V06549

Make from 0.375 (9.53) x 13 gauge [0.185 (4.70) ID]to 18 gauge [0.277 (7.04) ID] steel tubing

2.01 1.99(51.05 50.55)

0.340 0.339(8.64 8.48)


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36

65. CLBT 750 DUAL MODE TRANSMISSION WITH DROPBOX

The transfer gear housing adapter used with the dropbox has been slightly changed.

As a result, the CLBT 750 dropbox transmissions S/N 24218 and later will no longer

require the tubular spacer. The boss formerly located at the governor pressure tap has

been shortened. The new transfer gear housing adapters will appear to have a

recessed governor pressure tap boss. The earlier transfer gear housing adapters can be

used but the tubular spacer must also be used.

The following chart summarizes the above:

With

Tubular Spacer

Without

Tubular Spacer

S/N 24218 and Above X

S/N 24217 and Below XRecessed Governor Pressure

Tap Boss X

Early Model Governor

Pressure Tap Boss X


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37

71. GENERAL

A new step governor valve body assembly P/N 23010297 is available to replace the

former body assembly P/N 6883259. The new body assembly incorporates an

additional assembly bolt and washer to prevent oil seep leakage at the body to cover

plate gasket. Early model valve body assemblies P/N 6883259 that have oil seepage

can be reworked by an authorized Allison Transmission service outlet.

The part number changes necessary as a result of this change are as follows:

72. INTERCHANGEABILITY

Body assembly P/N 23010297 is fully interchangeable with early model body

assembly P/N 6883259.

Body P/N 23010293 non-serviceable serviced only with body assembly

P/N 23010297.

Cover P/N 23010294 is fully interchangeable with early model cover P/N 6883256. If

new cover P/N 23010294 is used with new body P/N 23010293, new gasket

P/N 23010295 must also be used. If new cover P/N 23010294 is used with early

model body P/N 6883257, gasket P/N 23010295 or 6883255 may be used.

Gasket P/N 23010295 is fully interchangeable with gasket P/N 6883255.

73. SPARE PARTS INFORMATIONThe following old parts are cancelled for customer service:

NewPart No. Qty

OldPart No. Qty Part Name

23010297 1 6883259 1 Body Assembly, Step Governor Valve

23010293 1 6883257 1 Body, Step Governor Valve

23010294 1 6883256 1 Cover, Step Governor

23010295 1 6883255 1 Gasket, Step Governor179849 4 179849 3 Bolt, 38-16 x 212Hx Hd

103321 4 103321 3 Lockwasher, 38

Part No. Part Name

6883259 Body Assembly, Step Governor Valve

6883255 Gasket

6883256 Cover

RELEASE OF STEPGOVERNOR VALVEBODY ASSEMBLY

P/N 23010297

SECTION

VII


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81. GENERAL

A manual/automatic kit is available for the 750 Series transmission which permits the

selection of either fully automatic or manual step operation. This permits a mobile rig

to be roaded in fully automatic and worked with manual step control for speed

selection.

This dual mode kit is P/N 6883932 and is fully described in Allison Transmission

Instruction Sheet 109 and SIL 29-TR-82. For manual/automatic control, the kit and

two additional components must be installed and operated in conjunction with the

normal range selector shaft. The separate step governor valve must be operated in

synchronization with the range selector shaft and a mode shift valve connected in the

transmission hydraulic system must activate to change the mode of operation.

Modifications to the transmission hydraulic system are necessary and specified in the

kit instructions. The special step governor valve is supplied in the kit. The mode shift

valve is specified but is furnished by the customer. The dealer, or customer, is

instructed to mount and link these valves on the transmission. Currently, there are two

major suppliers of the range shifters; Mannesmann Rexroth Corporation (refer to

Paragraph 82) and Bennett Enterprises, Inc. (refer toParagraph 83).

82. MANNESMANN REXROTH CORPORATION SHIFTER

A Mannesmann Rexroth Corporation pneumatic control system is available for dual

mode operation of the 750 Series transmissions, HT 750DRD and CL(B)T 750.Instructions permit roading a vehicle only in automatic mode. An interlock is

recommended to prevent manual step operation when the vehicle is being roaded.

The Mannesmann Rexroth system provides this feature in the form of a station select

system which shifts to automatic mode whenever the driving control valve is supplied

with air pressure. The system shifts to manual step mode whenever the drawworks

control valve is pressurized. A general schematic of the Mannesmann Rexroth control

system is shown in Figure 81.

For assistance, contact:

Mannesmann Rexroth Corporation

1957 Mercer Road

Lexington, KY 40511

Phone: 606-254-8031

MANUAL/AUTOMATICOPERATION ON OILFIELD EQUIPMENT

SECTION

VIII


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39

Figure 81. Mannesmann Rexroth Corp. Shifter Control Schematic


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40

A Mannesmann Rexroth Corporation bracket kit P065274 is available for mounting

the multi-position cylinder, step governor valve and the mode shift valve to the

transmission. It consists of a mounting bracket and the necessary linkage to mount

and actuate the range selector shaft and step governor valve simultaneously as

required. The bracket is attached to the two machining lugs on the selector shaft side

of the transmission(Figure 81). The Mannesmann Rexroth multi-position cylinderprovides the seven increments of stroke to position the selector shaft and step

governor valve. The assembly is mounted to the side of the transmission and projects

about 4 inch (102 mm) outside the transmission envelope in places. There is sufficient

clearance for most typical installations.

The 7-position control system shown inFigure 81is available from Mannesmann

Rexroth and their authorized distributors as Mannesmann Rexroth Kit P/N P065459.

The Mannesmann Rexroth components included in the kit are the 7-position cylinder,

rotair valves, pilotair valve, shuttle valves, bracket, and linkage kit.

7-Position Cylinder. The 7-position cylinder is a medium-duty pneumaticpositioning device that operates through seven predetermined positions of12inch (13 mm) increments with a total stroke of 3 inch (76 mm).

Maximum operating pressure is 150 psi (1034 kPa) within temperature rangeof 40200F (4093C). The cylinder piston rod reaches its various positions

in response to pressure being supplied to the cylinder ports, as shown in

Figure 82. The 7-position cylinder has reverse at the full extended position of the rod and

is spring-returned to neutral (next position in from reverse) from any position.

The HT 750 transmissions which these cylinders control, have the fully

automatic or drive position adjacent to neutral. The corresponding position is

5 on the 7-position cylinder. However, sequential order of cylinder positions is

a function of the P Number Rotair valve used.

The forces developed by the cylinder are functions of the air pressure applied

to the exposed piston areas and are tabulated for rod movement to the variousstroke positions as shown inFigure 82.The internal spring returns the piston

rod to its neutral position when air pressure is intentionally or unintentionally

exhausted from all control lines. This safety feature returns the transmission

to neutral if the air supply is lost.

Operator Controls. The basic Mannesmann Rexroth pneumatic multi-position control system consists of a multi-position power cylinder explained

above and a rotary type selector valve. An air supply pressure in the range of

90150 psi (6201034 kPa) is connected to the rotary valve. For each handleposition of the rotary valve, a different combination of the air lines is

pressurized, causing the cylinder to move to corresponding positive positions

and hold in these positions.


48/64

41

Figure 82. Cylinder Cross Section and Air Supply Schedule

The rotary type selector valve consists of a subplate portion containing airstrainers in each port connection, a seat and rotary disc valve section, a handle

operating section containing the handle labyrinth and position detents, and an

interlock switch section with a neutral start switch depressed only when the

handle is in the Nposition. The open labyrinth design permits the handle to be

moved quickly between desired positions and to Nposition. Detents for eachposition permit the operator to feel the handle location for each selection.

When the handle is released, it spring offsets between two pins to help prevent

inadvertent operation.Figure 83 details a cross-section of the rotary type

selector valve.


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Figure 83. Mannesmann Rexroth Corp. Rotary Type Selector Valve

83. BENNETT SHIFTER

The Bennett shifter manual/automatic adapter is specifi

cally designed to assureprecise, trouble-free conversion from automatic transmission to manual powershift

transmission.

For assistance, contact:

Stone-Bennett, Inc.

1419 Upfield Drive

Carrollton, TX 75006

Phone: 972-446-2046Fax: 972-446-2031

Coupled with the Allison 750 Series transmission and the Allison manual/automatic

option kit P/N 6883932, the Bennett shifter manual/automatic adapter synchronizes

the linear movement of the selector shaft of the step governor valve (furnished with

the Allison kit) with the rotating movement of the transmission range selector shaft.

This combination allows the transmission to operate accurately and effectively into

different modes:

The manual powershift mode, which allows upshifts to be made regardless oftransmission output speed and prevents automatic downshifts.

The normal automatic operating mode.


50/64

43

The complete mounting kit is designed to combine the Bennett shifter and the Allison

manual/automatic option kit into a precision operating unit. Selector valve levers are

available for either the HT or CLT transmissions.Figure 84 shows a typical

installation.

Figure 84. Typical Bennett Shifter Installation

A precise indicator system is built into the Bennett shifter and is directly connected

with the transmission range selector lever by mechanical linkages. Once the shifter is

in place, a light in the indicator panel assures the operator that the transmission is inthe range he has selected. This light is connected to the indicator system of the

Bennett shifter and forms a direct feedback system operated either electrically or by

air power. Bennett can supply either an air range indicator system or an electrical

range indicator system.

Figure 85 illustrates a typical installation on an oil well servicing rig where the

transmission is operated in the automatic mode from the cab when on the road and

the manual power shift mode from the rear station when on location.

Bennett Shifter. The shifter mechanism, which is made by BennettEnterprises, Inc., can be actuated by either compressed air or hydraulic fluid

acting on opposing limited-travel steel pistons moving in aluminum cylinders.


51/64

44

In operation, the pistons of the shifter either extend or retract the drive rod ofthe shifter, which changes the ranges on the transmission. As either piston is

advanced by the applied air or oil pressure, it moves forward for a fixed-

distance full stroke against an opposing return spring until it hits a mechanical

stop. As it does, a spring-loaded pawl is extended out of the moving cylinder

to engage a ratchet tooth on a rack attached to the drive rod of the shifter. Thismoves the drive rod one stroke in the direction of the piston, which

corresponds to the next detent position on the transmission shift lever.

Figure 85. Schematic Diagram for a Two-Station Unit

As the air is exhausted from the cylinder at the end of the pistons stroke, thereturn spring sets the piston back to its starting position, simultaneously

retracting the pawl as it goes. To move the shift lever of the transmission

another step, the cylinder must be reactivated for an additional stroke.

Reversal of the shifts on the transmission is accomplished in the same step-

wise manner by activating the opposing cylinder on the shifter mechanism. Awiper arm moving across electrical contacts on the shifter cover sends signals

to the control panel to tell the equipment operator what position the gear shift

lever is inFigure 86 is a cutaway view of the Bennett shifter.

Operator Controls. As with any product fulfilling a variety of roles andapplications, certain additional add-on features are useful. To enable the user

to tailor any of the basic Bennett shifter models to his individual

requirements, an option list is available. The following are some of the more

popular options:

1. Indicator lights connected directly to the electrical contacts in the shifter

provide the operator with a positive indication of the range of the

transmission (Figure 87).

2. For instantaneous shift to neutral or any range, a special auxiliary cylinder

installation is available(Figure 88).


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45

Figure 86. Bennett Shifter Cutaway

Figure 87. Range Indicator Lights

Figure 88. Quick Shift Cylinders

TRANSMISSION

5

31R

6

42N

BENNETT ENTERPRISESDALLAS, TEXAS

V06549


53/64

46

3. A downshift inhibitor valve can be added to the Bennett shifter to prevent

downshifting when the torque converter of the transmission is in lockup.

4. When an electrical range indicator system is used, the neutral terminal of

the shifter provides the necessary electrical path for installation of a

solenoid switch. This prevents starting of the engine except when the

transmission is in neutral.

84. PREVENTIVE MAINTENANCE ON SHIFTERS

Careful attention must be given to the external linkages connecting the transmission

range selector, step governor valve and shifter. All three components must be in the

same detent at the same time. Otherwise, an improper shift could occur which could

fail the transmission.

85. MODE SHIFT VALVES USED IN MANNESMANN REXROTH ANDBENNETT SYSTEMS

Most Mannesmann Rexroth and Bennett systems require two mode shift valves;

either Eaton or Eagle Equipment valves (refer toParagraph 61). The system is

designed to operate the transmission in the manual mode when air is supplied to the

shift valve. When air is exhausted, or not applied at the mode shift valve, the

transmission will operate in the automatic mode.

In some cases, a Beckett valve will be used with a Bennett shifter. In this case, the

transmission operates in the manual mode when the air to the mode shift valve is

exhausted, or not applied. When the automatic mode is desired, air is applied to the

Beckett shift valve. A schematic of the Beckett valve circuitry is shown inFigure 89.

Figure 89. Mode Shift Valve Schematic

1

2

4

AUTOMATIC MODE(AIR APPLIED)

LEGEND: = Blocked Port

1 = LINE 1 inFigure 612 = LINE 2 inFigure 614 = LINE 4 inFigure 61

MANUAL MODE(AIR EXHAUSTED)

1

2

4

V06558


54/64

47

91. PRESSURE TAP LOCATION

Since the introduction of the CLBT 750 transmission, there have been several

changes resulting in different locations for checking specific oil pressure schedules.

Therefore, to avoid confusion and the possibility of checking a pressure schedule at

the wrong location, refer to Figures 91through94 for location of the pressurecheck points.

Figure 91. Transmission Checkpoints Without Retarder

LOCKUPLUBE MAINFRONTGOVERNOR

LOCKUP MAIN

FRONTGOVERNOR

SEPTEMBER 1974PRIOR TO S/N 5940

JANUARY 1976PRIOR TO S/N 11250

SEPTEMBER 1974AFTER S/N 5939

JANUARY 1976AFTER S/N 11249

LOCKUPLUBE MAIN

FRONTGOVERNOR

LOCKUPLUBE

MAIN

FRONTGOVERNOR

V03605.01

TROUBLESHOOTINGCLBT 750

WITH DUAL MODE

SECTION

IX


55/64

48

Figure 92. Transmission Checkpoints With Retarder

NOT ACTIVE

NOT ACTIVE

LUBE

LUBE

LOCKUPMAINFRONT GOVERNOR

NOT ACTIVE

MODULATORLOCKUPMAINFRONT GOVERNOR

FRONT GOVERNOR

SEPTEMBER 1974PRIOR TO S/N 5940

EFFECTIVE APRIL 1975AFTER S/N 8249

SEPTEMBER 1974AFTER S/N 5939

NOT ACTIVE

MODULATORLOCKUPMAIN

V03606.01


56/64

49

Figure 93. Transmission Checkpoints With Retarder

And Engine-Driven PTO

APRIL 1975PRIOR TO S/N 8250

APRIL 1975AFTER S/N 8249

EFFECTIVE JANUARY 1976AFTER S/N 11249

V03607.01

NOT ACTIVE

NOTACTIVE

LUBE

NOT ACTIVELUBE

LOCKUP

LOCKUP

MAINFRONTGOVERNOR

MAINFRONT GOVERNOR

FRONT GOVERNOR

MODULATORLOCKUPMAIN

LUBE


57/64

50

Figure 94. Transmission Checkpoints All Models

NEUTRAL STARTSWITCH LOCATION

REAR GOVERNORPRESSURE

REVERSE SIGNALSWITCH LOCATION FOURTH CLUTCH (HT)

FIFTH CLUTCH (CLT and CLBT)

REAR GOVERNORPRESSURE

GOVERNOR FEED

E03608.02


58/64

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92. TROUBLESHOOTING DUAL MODE CIRCUITRY

The following items should be checked before attempting to troubleshoot the

circuitry:

Verify that engine idle speed is not lower than 650 rpm.

Verify that the transmission has the correct oil level. Refer toSection 5,Figures 52 and53.

Verify that the air system used to p

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